The vortex shedding flowmeter technology provides a unique advantage in bringing forth a new generation flowmeter that measures volume and mass flow rates as well as the fluid density, as the frequency of vortex shedding is proportional to the fluid velocity and the fluid dynamic reaction to the vortex shedding is proportional to the dynamic pressure of the fluid flow that is equal to one half of the fluid density times the squares of the fluid velocity. No other flowmeter technologies employing a single flow sensor provide flow data of dual nature like the vortex shedding flowmeter. There is little doubt that in near future, there will be a very wide spread use of the vortex shedding flowmeter as a three-in-one flowmeter that measures volume flow rate and fluid density. At the present time, there are a few outstanding vortex sensing technologies as well as numerous mundane vortex shedding flowmeter technolodies, which are feasible for constructing flowmeters of flow passage diameter greater than three quarters of an inch or larger. There are extensive demands for flowmeters of flow passage diameters less than three quarters of an inch and greater than three sixteenth of an inch in the chemical, pharmaceutical and food processing industries.